I had also located some Tritium "Emergency Signs" from sources other than McMaster, price unknown. Would they be an adequate source of Tritium, Would it be legal? How might one retrieve the Tritium without contamination/loss? Is it worth the expense/danger/hassle? Too many questions. What is the real ownership status of the lights, are they owned outright by the buyer or are they required to be returned at the end of their useful life. Having worked in the production of microwave ovens (don't laugh, they are listed as "radiation emitting devices") I've witnessed some of the Governments "long arm" in controlling radioactive devices. It seems you might be required to provide proper user documentation no matter what your source may be and if that were to be the case, may as well by it from a direct source. Does anyone know the legal ramifications of acquiring from a secondary source?